Filtering apparatus for air and the like



May 8, 1923. 1,454,248

5. J. MARX FILTERING APPARATUS FOR AIR AND THE LIKE I Filed July 16 1919 3 Sheets-Sheet 1 L i. 8 2. 0 4 t J u 7 J 5 w T A" w n1 w .h E5 M3 Mm L E H T D M m R1 H mm N\ TI mun m JM n sww AH GF N I R E T L I F May 8, 1923.

May 8, 1923.

S. J. MARX FILTERING APPARATUS FOR AIR AND THE LIKE 5 Sheets-Sheet 5 5 iven??? of the bag type, and has eararrrrca STEPHEN J. MARX, 0F OLEV 1 D, OHIO, ASSIGNOR TO THE CLEVELAND AIR ENG-I- NEERING COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

FILTERING APPARATUS FOR AIR AND THE LIKE.

Application filed July 16, 1919. Serial No. 311,195.

T 0 all whom it may concern:

Be it known that I, STEPHEN J. MARX, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Filtering Apparatus for Air and the like, of which the following is a full, clear, and exact description.

This invention relates to air and gas filters for its chief object to improve the efliciency and reliability of apparatus of this character. The invention relates particularly to a pneumatic shaker for; agitating or shaking the bags at the same time that the direction of air through the bags is reversed to free the bags of dust and other foreign particles collected in the meshes or interstices of the bags during the filtering operation. The invention has particular reference also to the distributor by which air is distributed successively to the shaking cylinders and also to the pneumatic damper controlling cylinders of the several bag compartments.

The invention may be briefly summarized as consisting in certain novel details of construction, and combinations and arrangements of parts which will be described in the specification and set forth in the appended claims.

In the accompanying sheets of drawings, Fig. 1 is a diagrammatic plan view showing a bag filtering apparatus composed of four bag compartments, of which there may be any number, constructed and operated in accordance with my invention; Fig. 2 is a diagrammatic plan view illustrating the manner in which the air is reversed through the bags of one compartment while the bags of the other compartments are filtering, this view showing the inlet manifold and omitting the outlet manifold; Figs. 3 and 4 are vertical sectional views, also diagrammatic, showing a compartment while filtering and While shaking Figs. 5 and 6 are elevational views with Fig. 5 partly in section. showin a portion of one compartment with the bag shaking and damper controlling mechanism at the top thereof; Fig. 7 is a sectional'view of the bag shaking mechanism; Fig. .8 is a view partly in section and partly in eleva tion showing the distributor which supplies air successively to the cylinders of the different shakers and damper controlling cylinders arranged on the various compartments; and Fig. 9 is a face view, partly in section, of the distributor.

Filtering apparatus constructed in accordance with my invention includes any nu1nber of compartments, four only being shown for convenlence, each compartment comprising a vertical cylindrical casing 10 containing a number of cylindrical bags 11, com posed of suitable foraminous material, such as cloth, through which the air passes while being filtered. At the lower end of the casing 10 is a hopper 10 to which the inlet duct carrying dust laden air or gas is designed to be connected, and which is provided at the bottom with a normally closed door or gate indicated at 10 for the discharge of the dirt separated from the air which passes through the compartment.

The bags 11 are open at their lower ends, and are secured at their lower ends to a suitable plate or other stationary holding member 12 to which the lower ends of the bags are secured in any suitable manner. The upper ends of the bags are closed by suitable disks of wood or metal to which the bags are firmly secured, and the bags are supported by a series of hangers 13, suspended from a bag ring 14, part being secured directly to the ring. and part to cross arms 14*, the hub or center of this ring, indicated at 14 in Fig. 7, being secured. by nuts 15, or equivalent fastening means to the lower end of a piston shaft 16 which passes through the base of the cylinder casting 17. the same being attached to the top 10 of the compartment casing. this cylinder casting and piston shaft forming a part of a pneumatic shaker to be referred to presently. During filtering. the nut or other abutment on the piston shaft 16 is held up against a boss 17 of the base of the cylinder casting, as shown in Fig. 7. When the bag ring is elevated and held up against the boss 17*. the bags are taut. I

Dust laden air or gas containing foreign particles to be filtered out is supplied to the lower portions of the several compartment casings by means of a duct or manifold 18. The air or gas (hereinafter referred to as air,'for convenience) enters the lower open ends of the bags and passes upwardly along the bags and out through the bags. and is thereby filtered. this action being indicated in Fig. 3. The cleaned air cylinder 22 leaves the upper ends of the compartment casings by way of an outlet chamber 19, connected to an outlet manifold or duct 20, which is common to all the several compartment casings, and through which the air is drawn by a suction fan, not shown. Each outlet chamber has a pivoted or swinging damper 21, which during filtering is in the position shown in Fig.3, so as to allow the air to pass in the direction indicated by the arrows in Fig. 3, but this damper may be swung to the position shown in Fig. 4 so as to shut ofi the up er part of the compartment casing from the outlet manifold 20, and at the same time open the upper part of the compartment casing to the atmosphere. en this takes place, the air reverses through the compartment, as indicated by the arrows of Fig. 4:, this reversal being due to the fact that the air is normallv drawn through the inlet manifold 18, up through the compartments, and out by wa of the outlet manifold 20 by a suction fan connected to the latter, so that when the damper is swung to the position shown in Fig. 4, that is to say, from normal filtering position to shaking position, air is drawn by the suction fan down through the compartment and into an inlet manifold 18.

Each damper 21 is controlled by two air cylinders including a cylinder 22 containing a piston which is connected by an arm or rod 23 to one end of the damper shaft, air being at all times supplied to this cylinder so that it constantlv tends to hold the same in its normal position shown in Fig. 3. The damper is swung to shaking position by the other cylinder 24: which is somewhat larger than the first-named and contains a piston which is connected to the opposite end of the damper shaft. Air is supplied to this cylinder at the same time that it is supplied to the cylinder of the bag shaker only at intervals, or when shaking is desired, in which event this cylinder overcomes the relatively small cylinder, and thus swings the damper to shaking position until the alr supply is shut off. in which event the at once swings the damper back to normal filtering position.

Taking up next the shaking mechanism, this includes a main air cylinder or cylinder casting 17, whose base is mounted on the top of the compartment as before stated. This shaking cylinder receives the piston shaft 16 which has attached to it a piston 25 and carries just above this piston a ring valve 26 which surrounds the reduced upper end of the piston shaft, and is so mounted on this shaft that there may be a certain degree of lost motion between the valve and the shaft. The cylinder has an inlet boss 27 with a port 27 leading to the interior of the cylinder, this port being normally just above the piston 25. Likewise the cylinder or crossar 29 the cylinder restate has a boss 28 with an exhaust port 28*, this port being a short distance above the inlet port 27, and being normally closed by the valve 26.

The lower part of the shaker cylinder 17 is slotted, and extending transversely across this portion of the cylinder, and having its ends pro'ecting beyond the latter is a yoke ivoted at 29 to the shaft 16, the outer en s of the bar being engaged by two sprin seats 30, between which an ase are two coil springs 31, the function of which is to return the piston, piston shaft and bag ring to upper position and to hold them in this position when the air supply on top of the piston is shut ofi following the supply of air through the distributor to the cylinder, as will be explained more fully later. lit is not essential that there be only two of these springs 31, though two are thought to be ample, it being important that there be at least two of them, and that they be located outside the confines of the cylinder through which the piston shaft 16 passes, so that repairs, replacements, or adjustments can be easily effected. The springs'may be adjusted by adjusting screws 32 which pass through the outer ends of the yoke 29 into the spring seats 30. lit is a matter of importance that the slotted portion of the cylinder through which the cross-bar 29 extends, serves as a guide for the latter and thus prevents the piston shaft and bag ring from turning or swinging during the shaking ,period, and thus prevents excessive strains being imposed in the bags,

Taking up next the construction of the distributor, it will be observed by reference to! Figs. 8 and 9 considered in connection with Fig. 1, that the shaking operations ot the different compartments are controlled through an air distributor which is preferably mounted on top of one of the compartment casings, as indicated in Fig, 1, but which can be placed in any convenient location. The rotor member of this distributor is driven by a pulley 33, shown in Fig. 1 (or by a motor if desired) which drives a shaft 34 connected by gearing, in this in-, stance, worm gearing, including a worm wheel 35 (see Fig. 8) enclosed within a gear casing 36, and connected to a shaft 37 which extends laterally into one side of a distributor casing 38. This distributor casing includes three main parts consistingof a plate 38*, through which the shaft 37 passes, this plate having a flan e bolted to the gear casing 36 as shown in ig. 8, and the casing includes also a main or body portion 38", and an annular plate 38 which is bolted to the side of the body rtion 38", and has at the axis of the distributor a threaded opening 39 to which an air suppl pipe is adapted to be connected. lltotata ly supported in are the flanged hubs of the plate 38 and body portion 38 of the distributor is a distributor rotor 40, composed of a hollow shaft, open at one end opposite and directly in line with the air supply opening 39 of the cover plate 38, and havin a radial hollow arm 40 on which is sli ingly disposed a distributor shoe 41, having an outlet slot 41. The end of the rotor shaft inside the cover plate 38 passes through a packing gland 42 which prevents leakage of air around the shaft to the interior space of the distributor casing, which may be, and preferably is open to the atmosphere through the medium of a port 43. Leakage of air between the shank of the sliding shoe 41 and the radial arm 40 of the distributor rotor is prevented by a Suitable packing, held in place by a gland member 44, forming in effect a part of the shank of the shoe.

The shoe is pressed radially outward partly by air pressure, but chiefly by means of a coil spring 45 surrounding the rotor arm 40, and located between the shaft of the rotor and the gland 44, and it is thus pressed yieldingly but firmly against the peripheral wall of the body portion 38 of the distributor casing. Formed on this wall, outside of] the peripheral surface engaged by the rotor shoe 41, are a series of outlet compartments 46 communicating with the interior of the distributor casing by slots 46 adapted successively to be brought into registration with a slot 41 of the distributor shoe as the latter is rotated, and these outlet compartments 46 have laterally disposed. openings 46 into which are adapted to be fitted air delivery pipes 47 (see Fig. 1) each leading to the inlet port of theshaker cylinderof a bag compartment, and by way of a branch pipe to the damper operating cylinder 24 for that compartment. While attention is being directed to Fig. '1, it might be mentioned that this view shows not only the pipe connections between the distributor and the shaker and damper operating cylinders of the different compartments. but it shows also a pipe line 48, connected to the main supply pipe, here designated 49, and to the several cylinders 22, whose purpose is to swing the dampers to normal closed position after the cessation of the shaking operations as before stated.

The distributor shown in Fig. 9 has provision for delivering air to the shaker and damper operating cylinders of ten different bag compartments; hence this distributor is adapted for filtering apparatus having ten or less bag compartments. Should there be ten compartments. a delivery pipe would be connected to each of the different outlet openings 46 of the distributor, but should there be less than ten bag compartments, part of the outlet openings 46" would be plugged.

In operation, as the rotor of the distrib utor is rotated, the delivery slot 41 of the distributor shoe is successively brought into registration with the peripheral slots 46 of the distributor casing, and hence air is delivered successively to the shaking cylinders and damper operating cylinders of .the different bag compartments, with the result that the bags of the different compartments are shaken one after the other, and at regular intervals, and at the same time that air is supplied to the shaking apparatus of each compartment, the damper is swung for that compartment so as to reverse the direction of air through the bags.

As the air is supplied to the cylinder of the shaking apparatus of any compartment, the piston 25 is forced downward, lowering the piston shaft and the bag ring so asto flex or loosen the bags, and while this is taking place the springs 31 are compressed. After a predetermined movement of the piston 25 relative to the valve ring 26 (and the extent of this movement'can be varied) an abutment, in this instance in the form of a nut 26 at the upper end of the piston shaft 16 strikes the hub of the ring valve 26, forcing the ring valve downward so as to close the inlet port 27 thereby cutting oil the air supply to the cylinder, and uncover the exhaust port 28 which allows the air now in the cylinder to escape, thereby relieving the pressure on the springs and reducing to atmospheric pressure the air in the c linder. Immediately the piston is elevate by the action of the springs 31, raising the piston shaft 16 and the bag ring, and causing an abutment just above the bag ring, and in this instance, in the form of a nut, to forcibly strike the boss 17 at the bottom of cylinder 17. This gives all the ba s in the compartment a violent shaking. is the piston rises, it elevates the ring valve. closing the exhaust port and again opening the inlet port. whereupon it is again driven down, and this is quickly followed b a restoration to the former position, imparting another sudden shake or jar to the bags. This is repeated a number of times with great rapidity before the slot 41 of the distributor shoe passes beyond the stationary slot 46 of the distributor casing, with the result that in this short interval of time the bags have been effectively relieved of the dirt and dust which the bags had collected during the previous filtering interval. The rotor of the distributor may be driven at any desired speed so that the shaking operations can be imparted successively to the bags of the different compartments at intervals which can be varied to suit the exigencies of any particular case.

The manner in which the air is exhausted at or about the instant that the air supply to the cylinder is cut off, is a matter of considerable importance for it is highly desirable that the pressure above the piston be reduced to substantially atmospheric pressure throughout substantially the whole upward stroke of the piston, and that the piston be not obliged to return against air pressure. Should it be desired to vary the length of the downward stroke of the piston before the air supply is cut off and the exhaust port is opened, this can be readily done by adjusting the position of the nut 26 at the top of the piston shaft, and should it be desirable to vary the adjustment of the springs so as to alter the severity of the different individual shaking movement, this can be readily done. Should the springs need replacement, the construction that I have provided permits this to be very readily accomplished without requiring that the particular compartment to which the dainaged shaking apparatus belongs be kept out of commission for any length oftime, for the construction is such that access can be had to the springs without dismantling much, if any, of the shaking apparatus.

The distributor likewise is exceedingly effective, there being absent an excessive amount of friction between the rotor and stator of the distributor, but nevertheless the distributor shoe is held outwardly against the stator of the distributor by the pressure of the spring 45, and partly by the pressure of air on the outer part of the shoe in such a manner that air is delivered to the several delivery pipes without any material leakage. Further the construction of the distributor is such that it has to a high degree the features of durability and reliability, which is equally true of the shaking mechanism. It might be mentioned in conclusion that immediately after the' slot 41* of the distributor shoe leaves each of the outlet slots 46 in the stator of the distributor, a small port 50 just behind the delivery slot 41 of the shoe comes into registration with the slot 46. this port extending across the face and down the side of the part of the shoe which engages the distributor casing, the function of this port being to relieve the pressure inthe pipe which has just served to deliver air to the shaking cylinder and damper swinging cylinder. and thus allow the damper restoring cylinder to swing the damper to normal position.

While I have shown the preferred form of my invention, it do not desire to be confined to the exact details shown, but aim in my claims to cover all modifications which do not involve a departure from the spirit and scope of my invention in its broadest aspects.

Having described my invention, I claim:

1. ln a filtering apparatus for air and the like, a casing containing a plurality of filtering bags through which the medium to be filtered is adapted topass, a pneumatic shaking mechanism comprising a cylinder and piston, a shaft connected to the piston and operatively connected to the ends of the bags in the casing whereby when air is admitted to the cylinder the piston and shaft will be moved in one direction, and a plurality of springs each positioned at one side of said shaft and acting to restore the piston and shaft to normal position when the air pressure is relieved.

2. In a filtering apparatus for air and the like, a casing containing a plurality of bags through which the medium to be filtered passes, a pneumatic shaking apparatus comprising an air cylinder at the top of the easin and containing a piston, a shaft connected to the piston and extending into the top of the casing and operatively connected to the bags, means for supplying air under pressure above the piston so as to lower the same, and means for restoring the bags, shaft and piston to. normal position when the air pressure is relieved, comprising a rross-member attached to the shaft, and a plurality of springs located between the said cross-member and the top of the casing.

3. In an apparatus for filtering air and the like, a casing containing a plurality of bags through which the mediuln to be filtered passes, a pneumatic shaking device comprising an air cylinder containing a piston, a shaft connected to the piston and operatively connected to the ends of the bags, a member carried by the shaft and extending transversely of the cylinder, springs between the ends of said member and the easing and serving to normally hold the bags taut, and means for repeatedly admitting and then exhausting air from the top of the cylinder.

t. In an apparatus for filtering air and the i like, a casing containing a plurality of bags through which the medium to be filtered passes, a vertically movable bag supporting and tensioning member COIlIlGtlZQd to the upper ends of the bags, a pneumatic shaking device comprising a cylinder at the top of the casing containing a piston with a shaft extending into the casing and attached to said bag supporting member, means for repeatedly admitting air to and exhausting it from the upper part of the cylinder, and means for restoring the piston, shaft and bags to normal position when the air pressure is relieved, comprising a cross-bar connected to the shaft beneath the piston, and a pair of springs at the ends of said crossbar on opposite sides of the shaft.

5. In an apparatus for filtering air and the like, a casing containing a plurality of bags-through which the medium to be filtered passes, a vertically movable bag sup porting member connected to the upper ends of the bags, a pneumatic shaking device comprising a cylinder at the top of the casing containing a piston with a shaft extending into the casing and attached to said bag supporting member, means for repeatedly admitting air toand exhausting it from the upper part of the cylinder, and means for restoring the piston, shaft and bags to normal position when the air-pressure is relieved, comprising a cross-bar connected to the shaft, and a .pair of'springs between the cross-bar and the top of the casing and engaging seats at the top of the casing and at the ends of the cross-bar;

6. In an apparatus for filtering air and the like, a casin containing a plurality of bags through which the medium to be filtered passes, a vertically movable bag supporting member connected to the upper ends of the bags, a pneumatic shaking device comprising a cylinder at the top of the casing containing a piston with a shaft extending into the casing and attached to said bag supporting member, means for repeatedly admitting air to and exhausting it from the upper part of the cylinder, means for restoring the piston, shaft and bags to normal position when the air pressure is relieved, comprising a cross member carried by the shaft, a pair of springs between the cross member and top of the casing, and means for adjusting individually the tension of thes r1n 7. 11 an apparatus for filtering air and the like, a casing containing a plurality of bags through which the medium to be filtered passes, a pneumatic bag shaking device comprising a cylinder contalnlng a p1ston, a shaft connected to the piston and operatively connected to the ends of the bags, means for supplying air to the cylinder, and

' means movable with the piston for cutting off the supply and exhausting the air from the cylinder after a predetermined movement of the piston in a downward direction.

8. In an apparatus for filtering air and the like, a casing containlng a plurality of bags through which the medium to be filtered passes, a pneumatic bag shaking device comprising a cylinder containing a plston, a shaft connected to the piston and opera tively connected to the ends of the bags, means for supplying air to the cyllnder, and means for cutting off the supply and exhausting the air from the cylinder after a predetermined movement of the piston 1n a downward direction, said means comprising aFvalve member loosely carried by the shaft.

9. In an apparatus for filtering air and the like, a casing containing a plurality of bags through which the medium to be filtered passes, a pneumatic bag shaking device comprising a cylinder containing a piston and having air supply and exhaust ports, a shaft connected to the piston andv operatively connected to the ends of the bags, means for supplying air to the cylinder, and means for. cutting off the supply and exhausting the air from the cylinder after a predetermined movement of the piston in a downward direction, said means comprising a valve member Within the cylinder having a lost motion connection with the shaft and piston.

10. In an apparatus for filtering air and the like, a casing containing aplurality of bags through which the medium to be ,ifiltered passes, a pneumatic bag shaking device comprising a cylinder containing a piston, a shaft connected to the eratively connected to the ends of the bags, means for supplying air to the cylinder, an'g means for cutting ofl the supply and exhausting the air from the cylinder after a predetermined movement of the piston in a downward direction, said means comprising a valve ring surrounding the piston shaft, and having a lost motion connection with the shaft.

11. In an apparatus for filtering air and the like, a casing containing a plurality of bags through which the medium to be filtered passes, a pneumatic shaking device therefor, comprising a cylinder containing a piston, a piston shaft operatively connected to the ends of the bags, said cylinder having air supply andexhaust ports, and a valve member adapted to be shifted by the shaft and arranged to cover the supply port and uncover the exhaust port when moving in a downward direction, and to uncover the supply port and cover the exhaust port When moving in the reverse direction.

12. In an apparatus for filtering air and the like, a casing containing a plurality of bags through which the medium to be filtered passes, a pneumatic shaking device therefor, comprising a cylinder containing a piston, a piston shaft operatively connected to the ends of the bags, sai cylinder having air supply and exhaust ports, and a valve member adapted to be shifted by the shaft, and arranged to cover the supply port and uncover the exhaust port when moving in a downward'direction and to uncover the supply port and cover the exhaust port when moving in the reverse direction, said valve being in the form of a ring engaging the cylinder wall and loosely engaging the piston shaft whereby the shaft may have a limited lost motion with respect to the valve.

13. In an apparatus for filtering air and the like, a casing containing a plurality of bags through which the medium to be filtered passes, an axially movable shaft connected to the ends of the bags, pneumatic shaking mechanism comprising a cylinder containing a piston connected to saidshaft, means for supplying and interrupting the ,supply of air to one end of the cylinder,

and means and shaft t pressure is 5 connected t ends of the for restoring the piston, bags 0 normal position when the air relieved comprising a cross-bar o the shaft and springs at the cross-bar, the cylinder having a slotted portion forming guides for the crossbar.

14. In a the like, a bags throu filtered passes, casing, means air to the distributor livery openings connected to the different shakers,

and a hollow rotor having an outstanding arm and a shoe slidably mounted thereon, sai 2O stator and (1 shoe engaging the wall of the having a distributor opening bags through which adapted to be brought into registration with said delivery openings of the stator.

15. In a filtering apparatus for air and the like, a plurality of casings containing the medium to be a pneumatic shaker for each casing, means for sucessively supplying air to the different shakers comprising a istributor, said distributor having a stator with a cylindrical wall provided with spaced defiltered passes,

livery openings adapted to be connected to the different shakers, and a rotor revolubly mounted in the stator and having an outstanding hollow arm With a shoe engaging the cylindrical wall of the stator, said shoe having a delivery opening, and means for supplying air to the rotor.

In testimony whereof, ll

my signature.

STEPHEN J. MARX.

hereunto aiiix 

